Antibiotic P.A. 132, and a microbiological process for its preparation, are disclosed in U.S. Pat. No. 3,113,074. The antibiotic is produced in a fermentation process using the microorganism Streptomyces roseogriseus, which has been deposited with the ATCC culture repository and given the accession number ATCC 12414. A subculture of this deposit is available to the public upon request to the American Type Culture Collection, Washington, D.C.
The structure of antibiotic P.A. 132 is disclosed in the paper entitled "The Structure And Absolute Configuration Of Pentalenolactone (PA 132)", by D. G. Martin et al., Tetrahedron Letters No. 56, pages 4901-4904, 1970.
The structure of P.A. 132 is as follows: ##STR2##